Article
Pharmacology & Pharmacy
Tobias W. M. Keil, Olivia M. Merkel
Summary: This article introduces a new coating solution based on choline-chloride for the measurement of size, polydispersity and concentration of positively charged nanoparticle formulations. The coating is validated and tested successfully using tunable resistive pulse sensing.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2021)
Article
Materials Science, Multidisciplinary
Anupama Rao Gulur Srinivas, Rafiq Hilali, Mona Damavandi, Jenny Malmstrom, David Barker, Eva Weatherall, Geoff Willmott, Jadranka Travas-Sejdic
Summary: This study successfully achieved the functionalization of TPU tunable nanopores using a one-pot strategy, with grafting of negatively charged PAA brushes through the Graftfast method and demonstration of grafting of neutral brushes. The functionalization was characterized using various analytical methods, confirming the increase in negative surface charge on the pore walls.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Nega Ejjigu, Khalid Abdelgadir, Zachariah Flaten, Cameron Hoff, Chen-Zhong Li, Dali Sun
Summary: This study successfully suppressed environmental noise in tunable resistive pulse sensing (TRPS) measurements by designing an external shield. The method overcomes challenges in quantifying extracellular vesicles (EVs) and improves detection of small-sized EVs.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Chemistry, Analytical
Wenwei Pan, Rui You, Shuaihua Zhang, Ye Chang, Feng Zhou, Quanning Li, Xuejiao Chen, Xuexin Duan, Ziyu Han
Summary: Nanochannel-based resistive pulse sensing (nano-RPS) system is widely used for high-sensitive measurement and characterization of nanoscale biological particles and biomolecules. However, fixed geometric dimensions and surface properties of nanochannel limit its detection capabilities. This study proposes a multi-module self-assembly (MS) strategy to shrink geometric dimensions and tune surface properties of nanochannels simultaneously, resulting in enhanced signal-to-noise ratio (SNR) and resolution for nanoparticle and viral particle detections.
ANALYTICA CHIMICA ACTA
(2023)
Article
Nanoscience & Nanotechnology
Tomoki Hayashida, Makusu Tsutsui, Sanae Murayama, Tomoko Nakada, Masateru Taniguchi
Summary: This study systematically characterized the effect of dielectric coatings on the capture-to-translocation dynamics of single particles in solid-state pores. By covering SiNx membranes with different coatings, the researchers were able to change the zeta-potential at the pore wall, leading to easier particle capture and slower translocation motion in the channel. These findings serve as a guide for engineering pore wall surfaces to optimize translocation dynamics for efficient sensing of particles and molecules.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Yukichi Horiguchi, Norihiko Naono, Osamu Sakamoto, Hiroaki Takeuchi, Shoji Yamaoka, Yuji Miyahara
Summary: Resistive pulse sensing (RPS) is an analytical method used to count particles from a small sample. In this study, a biosensing methodology on RPS was investigated by creating a sensing surface using polydopamine (PD) and using virus-specific ligands to monitor the translocation of biological particles. The research shows that the PD-based biosensor surface design is effective, and introduces the potential of the advanced RPS measurement system as a promising analytical technique.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Biophysics
Zoltan Varga, Monika Madai, Gabor Kemenesi, Tamas Beke-Somfai, Ferenc Jakab
Summary: Microfluidic resistive pulse sensing was used to determine the size distribution of SARS-CoV-2, and the results showed that it follows a log-normal function with a mean value of 85.1 nm, corresponding to the approximate diameter of the viral envelope.
COLLOIDS AND SURFACES B-BIOINTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Mi Zhang, Zachary D. Harms, Tine Greibe, Caleb A. Starr, Adam Zlotnick, Stephen C. Jacobson
Summary: The study introduced a novel fabrication method to create nanopores with circular cross sections in series and in plane with the substrate, aiming to improve the performance of resistive-pulse sensing in gene sequencing. The devices fabricated using this method demonstrated efficient detection of hepatitis B virus capsids, with a significant increase in relative pulse amplitude resolution observed.
Article
Materials Science, Multidisciplinary
Xinyang Miao, Yawen Yu, Xuecong Liu, Honglei Zhan, Kun Zhao, Wanting Lu
Summary: Electrically induced resistive switching in natural reservoir shale is demonstrated, showing repeated switching between high-resistance and low-resistance states. The switching is controlled by voltage settings, duration of excitation, and measuring voltages. The shale can be switched over 40 times with a high on/off ratio and low energy consumption. This phenomenon is also observed in tight sandstones and other sedimentary rocks. Rocks with tunable properties show promise for data storage applications due to their low cost, simplicity, and disposal ease.
RESULTS IN PHYSICS
(2023)
Review
Chemistry, Multidisciplinary
Somnath S. Kundale, Girish U. Kamble, Pradnya P. Patil, Snehal L. Patil, Kasturi A. Rokade, Atul C. Khot, Kiran A. Nirmal, Rajanish K. Kamat, Kyeong Heon Kim, Ho-Myoung An, Tukaram D. Dongale, Tae Geun Kim
Summary: Electrochemical synthesis is the most widely used technique for fabricating resistive-switching-based memory devices. This review article summarizes the electrochemical approaches for memory storage, neuromorphic computing, and sensing applications, highlighting their advantages and performance metrics. The challenges and future research directions for this field are also discussed.
Article
Nanoscience & Nanotechnology
Ziyu Han, Jiantao Liu, Zhanning Liu, Wenwei Pan, Yang Yang, Xuejiao Chen, Yunhua Gao, Xuexin Duan
Summary: This study introduces an IC-compatible method for fabricating a PDMS-based resistive pulse sensing device with embedded nanochannels, allowing for label-free analysis of biomolecules and bionanoparticles. The device was successfully tested with polystyrene micro- and nanoparticles, as well as for plasmid DNA detection and exosome analysis, demonstrating its potential for quantification of nanoscale biomolecules. The proposed nanochannel-RPS device and sensing strategy offer a cost-effective solution for large-scale manufacturing and accurate analysis of nanoscale particles and biomolecules.
Article
Chemistry, Multidisciplinary
Mireia Andonegi, Daniela Correia, Nelson Pereira, Manuel Salado, Carlos M. Costa, Senentxu Lanceros-Mendez, Koro de la Caba, Pedro Guerrero
Summary: With the sustainable development goals in mind, sustainable sensors based on natural polymers are necessary for the widespread use of the Internet of Things (IoT). This study focuses on collagen-based blends with different ionic liquids (ILs) and their effects on mechanical, thermal, and electrical properties. The best electrical response is achieved with a collagen/[Ch][Seri] sample, which exhibits lower tensile strength and higher elongation at break. The functional response of collagen-IL films on a resistive touch sensor shows potential for sustainable touch sensing devices.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Vardan Galstyan, Nicola Poli, Viacheslav Golovanov, Annalisa D'Arco, Salvatore Macis, Stefano Lupi, Eleonora Bolli, Saulius Kaciulis, Alessio Mezzi, Elisabetta Comini
Summary: There is a growing demand for nanocomposite materials with new functionalities in chemical gas sensors and catalytic devices. Green synthesis methods are widely used to reduce the hazardous effects on human health and the environment. This study reports the fabrication of a nanocomposite material based on WO3 and TiO2 with unique electronic band alignment and gas sensing properties.
ADVANCED MATERIALS TECHNOLOGIES
(2022)
Article
Biochemical Research Methods
Chien Hsu, Chih-Yuan Lin, Amer Alizadeh, Hirofumi Daiguji, Wei-Lun Hsu
Summary: This study theoretically analyzes the electrophoretic behavior of spherical particles near the entrance of a charged nanopore and summarizes the dominant mechanisms governing particle behavior for different conditions.
Article
Chemistry, Analytical
Rui Jia, Susan A. Rotenberg, Michael V. Mirkin
Summary: Extracellular vesicles have potential applications in cancer diagnostics and cell signaling. Electrochemical resistive-pulse sensing allows for direct detection and analysis of these vesicles, as well as monitoring the effects of therapeutic agents.
ANALYTICAL CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Hossein Rashidian, Matheu Broom, Geoff R. Willmott, Mathieu Sellier
JOURNAL OF THE ROYAL SOCIETY OF NEW ZEALAND
(2020)
Article
Acoustics
G. Schmid, M. J. Kingan, L. Panton, G. R. Willmott, Y. Yang, C. Decraene, E. Reynders, A. Hall
Summary: This paper focuses on the measurement and prediction of rainfall noise using the ISO standard method, presenting different force models for water droplet impact on a flat inclined surface. The best-performed models are incorporated into theoretical methods for noise prediction, showing moderate agreement with experimental measurements. Testing issues and suggestions for improvement are discussed, and theoretical models are used to investigate potential sources of error during testing with the ISO standard method.
Editorial Material
Multidisciplinary Sciences
Geoff Willmott, Mathieu Sellier, Cassidy Wilgar, Fabien Montiel
JOURNAL OF THE ROYAL SOCIETY OF NEW ZEALAND
(2021)
Article
Biophysics
Susav Pradhan, Raoul Solomon, Ankita Gangotra, Gleb E. Yakubov, Geoff R. Willmott, Catherine P. Whitby, Tracy K. Hale, Martin A. K. Williams
Summary: This study investigates the changes in material properties of nuclei extracted from MCF7 cells after knockdown of HP1α, showing that HP1α depletion significantly reduces the apparent Young's moduli of the cell nuclei. Additionally, different mechanical properties of the nuclei were observed when using different techniques, indicating that various components within the nuclei impact the overall mechanical response differently.
BIOPHYSICAL JOURNAL
(2021)
Article
Chemistry, Physical
Miguel Balzan, Ayoub Abdollahi, Frederick S. Wells, Geoff R. Willmott
Summary: Experimental study of vertical drop impacts of dairy-based solutions on smooth stainless steel surfaces was conducted using high-speed photography. Results showed that the behavior of different fluids during impact was mainly determined by their rheological properties. The maximum spreading diameter and the time to reach maximum spread were influenced by shear-thinning effects.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Mechanics
Matheu Broom, Geoff R. Willmott
Summary: This study uses high-speed photography to investigate the size and symmetry of the impact region and microbubbles formed when a water drop impacts a regular square array of hydrophobic micropillars. The results show that the size of the impact region is influenced by the pitch and Weber number of the pillars, and there is a transition from vertical to horizontal wetting near the edge of the drop's projected area. The impact region size can be described well by energetic and pinning transition analyses, but there are noticeable asymmetries, indicating the presence of cross-flows for gas and liquid escape. The findings of this study are relevant to various natural and industrial processes involving liquid drop impacts on rough surfaces.
Review
Chemistry, Applied
Miguel Martinez-Calderon, Thomas A. Haase, Nina Novikova, Frederick Steven Wells, Jeffery Low, Geoff R. Willmott, Neil G. R. Broderick, Claude Aguergaray
Summary: This study demonstrates the fabrication of superhydrophobic hierarchical micro- and nano-scale structures on painted surfaces using laser micro- and nanomachining. The complex chemical composition of paints plays a crucial role in determining the wettability and self-cleaning properties of the surfaces following laser ablation. This technique shows promise for industrial applications on exposed painted surfaces.
PROGRESS IN ORGANIC COATINGS
(2022)
Article
Genetics & Heredity
Nicola Lacalendola, Ayelen Tayagui, Matthew Ting, Jenny Malmstrom, Volker Nock, Geoff R. Willmott, Ashley Garrill
Summary: Zoospores are motile, asexual reproductive propagules that enable oomycete pathogens to locate and infect new host tissue. High osmotic stress causes different mechanical property changes in Type A and Type B zoospores, with Type A spores eventually returning to their original values, while Type B spores show initial stiffening in response to lower hyperosmotic stresses.
FUNGAL GENETICS AND BIOLOGY
(2022)
Article
Chemistry, Physical
Ayoub Abdollahi, Frederick S. Wells, Ali M. Sefidan, James N. Hewett, Mathieu Sellier, Geoff R. Willmott
Summary: This study experimentally investigated the vertical impacts of heated dairy product droplets on stainless steel surfaces. The results showed that the spreading of droplets during impact depended on the drying method and temperature.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Engineering, Electrical & Electronic
Nicola Lacalendola, Geoff R. Willmott
Summary: Ion pipette aspiration is a technique that combines micropipette aspiration and resistive pulse sensing to measure the mechanical properties of soft microparticles. By establishing a correlation between the mechanical properties derived from micropipette aspiration and the ion current measurement, the mechanical properties of particles can be predicted accurately.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Thermodynamics
Ali M. Sefidan, Mathieu Sellier, James N. Hewett, Ayoub Abdollahi, Geoff R. Willmott, Sid M. Becker
Summary: Spray drying is a commonly used method in the dairy industry to produce milk powder. In this study, an experiment and numerical model were used to study the drying kinetics of an industrial-scale skim milk droplet. The results show that the wet-core temperature distribution remains uniform, but the solute concentration distribution becomes uneven, suggesting a lower evaporation rate is recommended for a uniformly distributed solute in the final dried powder.
APPLIED THERMAL ENGINEERING
(2022)
Article
Physics, Fluids & Plasmas
Sina Safaei, Caleb Todd, Jack Yarndley, Shaun Hendy, Geoff R. Willmott
Summary: The self-assembly of Janus particles relies on precise interactions between neighboring particles, with orientations of the particles influenced by factors such as orientational entropy and solvent exclusion. A range of 40-55 degrees is found to be the most probable center-center-pole angles, with larger polar angles favored as the hydrophobic surface area increases. The relative azimuthal angle between the spheres is affected by solvent ordering.
Article
Materials Science, Multidisciplinary
Anupama Rao Gulur Srinivas, Rafiq Hilali, Mona Damavandi, Jenny Malmstrom, David Barker, Eva Weatherall, Geoff Willmott, Jadranka Travas-Sejdic
Summary: This study successfully achieved the functionalization of TPU tunable nanopores using a one-pot strategy, with grafting of negatively charged PAA brushes through the Graftfast method and demonstration of grafting of neutral brushes. The functionalization was characterized using various analytical methods, confirming the increase in negative surface charge on the pore walls.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Chemistry, Physical
Sina Safaei, Shaun C. Hendy, Geoff R. Willmott
Article
Physics, Fluids & Plasmas
Geoff R. Willmott, Alice Briole, Florence Szczepaniak
